LOS ANGELES, Calif. (FOX 11 / CNS) - A sea of humanity moved through the streets of downtown Los Angeles on Monday for the annual May Day march, with organizers and participants saying distaste for the presidential policies of Donald Trump led more people than usual to take part.

Tens of thousands of people gathered in MacArthur Park for the march dubbed "Resist Los Angeles," designed to be a show of "resistance, unity and defiance" against such White House policies as ramped-up enforcement of
immigration laws and an effort to build a massive border wall.

"Immigrant communities that are very vulnerable right now, they're going to have all of us to support them and showing the world and our president that they're not alone and that we'll fight for their rights," said demonstrator Cristina Hernandez.

Many said Trump inspired them to march for the first time in their lives, like a retired teacher named Robyn. She would only identify herself with her first name and told FOX LA she's taken part in the women's and science marches since Trump took office.

"I don't know that the White House is going to hear us but I hope that many other people will be encouraged to resist because we're going to need a huge movement to undo the damage that they are doing," said the former educator.

"We do it through independent movements," said John O'Brien, who calls himself a long time activist. "That's how we got the eight-hour (work) day; that's how we got the women the right to vote; that's how we ended slavery."

Various organizations that have planned marches in the past joined forces this year, uniting under the banner "May Day Coalition of Los Angeles" and organizing the march from MacArthur Park to Los Angeles City Hall.

It marks the first time in more than 10 years there has been such unity among organizers of May Day marches.

Trump supporters chanted slogans including "Put America first" and "USA," while some carried signs with messages such as "Repeal Obamacare" and "Trump -- Make America Great Again!" Led by a phalanx of Los Angeles police officers, the Trump group marched from the Federal Building to LAPD headquarters.

At the corner of Spring and 1st by Los Angeles City Hall, there was tension as a large group of Trump supporters and a group of May Day demonstrators had to be separated by a police skirmish line as tempers flared.

At one point, two men got into a fight. It quickly calmed down, though there were still people from both sides yelling at each other and making gestures.

Up the street, directly in front of City Hall, Mayor Eric Garcetti and others spoke to the May Day Protestors saying Los Angeles will be a city of justice.

Some, like May Day demonstrator Alan Garcia, didn't have much appreciation for the Trump supporters, though he admits they have the same right as he when it comes to speaking out.

"Absolutely, they have every right to say and protest what they want, but obviously they go to events where they’re not welcome,” said Garcia.

Others steered clear of the corner like 17-year-old Alica Chavez. She's a U.S. citizen, but has members of her family from Mexico who are undocumented. She’s worried about having undocumented family members deported and that’s why she stood there with a sign. She told FOX 11 she has sleepless nights "especially when Trump was first elected."

"I cried a lot because I was scared.”

Police did not give crowd estimates, but said it was far fewer than the 100,000 predicted. There were two arrests, one person for throwing a rock and another for arson after burning a flag in front of LAPD Headquarters.

There were 19 people who needed paramedic help. Heat was an issue for some people. It was unclear of the issues of those who asked for help, but eight were taken to local hospitals.

Former Los Angeles Mayor Antonio Villaraigosa, a candidate for governor, was among those taking part in the march.

"This year you're going to see an unprecedented number of people here in Los Angeles, primarily because of what's going on with Trump and his administration -- the ban, the wall, the talk of deporting 11 million people. Nobody's ever done that anywhere, I think for all of those reasons you're going to see an outpouring of people today."

Jo Reitkopp, chair of event organizer "Make California Great Again Inc.," said Trump supporters wanted to "step up and stand for our country and its Constitution ... for which millions of USA military men and women have lost their lives."

LAPD Chief Charlie Beck vowed that officers would be out in force to ensure the demonstration remains peaceful. He asked marchers to remember that his officers are in support of them and are not representatives of the federal government.

"My message is this: I know there are a lot of folks that are upset about recent immigration issues, have other issues with the federal government. You know, remember this is our city. Your police department supports you," Beck said during a recent appearance "We depend upon your cooperation. And let's make this a demonstration of L.A. unity and not the things that divide us."

Representatives from some community groups have called for a general strike in conjunction with the marches, even encouraging students to either not attend school or walk out of classes. There was even a call for the Los Angeles Unified School District to close for the day, but the district rejected the request.

"At the heart of this decision is our unwavering commitment to keep kids safe," LAUSD Superintendent Michelle King wrote in a letter in early April. "Civic engagement undeniably plays a vital role in our democracy, and we embrace the rights of all students, families and employees to unite and magnify their voices locally so that their messages can resonate on a larger scale.

"Nevertheless, schools continue to be the safest places for students to incubate an interest in civic engagement, and we encourage all schools to use May 1 as an opportunity to discuss matters of civic importance," King wrote.

Some students have taken part in walkouts during past May Day events, but it was unclear if any similar actions were planned.